The above-identified U.S. patent application Ser. No. 296,368 discusses various patents disclosing methods and apparatus for forming, molding, filling and sealing a container. Further, that U.S. patent application discloses a container, as well as apparatus and methods for forming the container, wherein a stopper or other insert is sealed in the top of the container.
Specifically, a length of hollow tube parison is first extruded between the main mold halves of a mold assembly. Then, while positioned between the main mold halves, a parison portion is cut from the extruder and the mold halves are moved to a station for blowing, molding and filling a container. Here the cut length of parison is positioned below a blowing and filling nozzle where the parison is molded into a container and then filled.
The stopper is initially carried by an insertion apparatus that has an insertion member in the form of a cylindrical arm. When the blowing and filling nozzle has been completely removed from the top opening of the filled container, the insertion member that is carrying the stopper is moved to position the insertion member and stopper over the container. The insertion member is then moved downwardly to deposit the stopper within the opening of the upwardly extending portion of the parison tube.
Then, sealing molds are closed to form the upper portion of the parison around the stopper to partially encapsulate the stopper. In one form of the disclosed method, a frangible web is formed by the sealing molds in a circumferential portion of the parison around and above the stopper while using the insertion member as an anvil.
A break-off tab or overcap may be subsequently formed above the stopper and frangible web, after the insertion member has been removed from the parison tube, by an additional set of upper sealing molds after the insertion member is retracted. When the container contents are to be dispensed, the tab or overcap may be broken away at the frangible web to expose an upper surface of the stopper and to permit the stopper to be removed.
Although the above-discussed container and insert structure, as well as the method and apparatus for fabricating such a structure, are satisfactory in many applications, the inventor of the present invention has found that it would be desirable to provide a container with a stopper or other insert at the top of the container wherein the frangible web is located around the insert instead of above it.
Further, it would be desirable in some applications to provide such a container and insert structure without the container material extending above the insert. This would permit the container and insert structure to be fabricated with less material.
Additionally, it would be advantageous to provide in some applications a method and apparatus for sealing a container with a multi-piece insert wherein the top of the container is hermetically sealed to each piece of the multi-piece insert and wherein a portion of at least one of the insert pieces projects beyond the container and is exposed so that it may be manipulated to open the container. With such a container and multi-piece insert structure, it would be desirable to provide a frangible web in the container material around at least one of the insert pieces to facilitate opening or fracture of the seal when desired.